Fetal Alcohol Spectrum Disorders (FASD) result in neurodevelopmental deficits and lifelong disability; they are a leading cause of preventable birth defects in the U.S. According to the CDC, any sexually active woman of reproductive age who drinks alcohol and does not use effective contraception is at risk for an alcohol exposed pregnancy (AEP) that could cause FASD. By this definition, American Indian and Alaska Native (AIAN) young women are especially vulnerable to AEP, with high levels of alcohol consumption and sexual risk taking compared to their counterparts in other race/ethnic groups. Although an estimated 72% of AIAN young women live in urban areas, very little research has yet included them; urban AIAN needs are often ignored in research aimed at developing, implementing, and evaluating culturally appropriate services. Recent research indicates that mobile health (mHealth) interventions may offer a promising mechanism for delivering effective interventions to hard-to-reach populations. The goal of this project is to expand reach and services to urban AIAN young women through mHealth technology to prevent AEP and FASD. The proposed project builds on a prior NIAAA-funded project which used intensive community-based participatory research (CBPR) methods to adapt CHOICES, an evidence-based brief AEP intervention supported by the CDC, to American Indian Youth CHOICES (AIY-C). AIY-C contains features that make it highly amenable to mHealth approaches, including a framework for integrating diverse cultural teachings, few modules of short duration, and concrete opportunities for goal-setting and achievement. Innovative for this population is the plan to recruit young AIAN women from major urban areas in the US through social media?and to deliver AIY-C via mobile devices, increasingly ubiquitous among AIAN young adults. While social media recruitment and mHealth interventions are not new, only very recently have they been used with AIAN populations. We will partner with urban AIAN organizations to guide us through social media recruitment strategies, mHealth intervention translation and implementation, and evaluation in urban AIAN settings. We propose 3 specific aims: (1) Develop and pilot social-media-based recruitment strategies for urban AIAN young women; (2) translate AIY-C for mHealth delivery through an iterative and theoretically driven process and pilot the developed translated mHealth AIY-C intervention; and (3) recruit 700 (final N=525) urban AIAN young women using identified social media strategies, and conduct an RCT to rigorously evaluate the effectiveness of the mHealth translation of AIY-C for preventing AEP and FASD. The proposed project promises expansive reach to AIAN young women to address significant yet preventable public health concerns ? AEP and FASD; importantly, the project also promises to advance a blueprint for preventive intervention research with urban AIAN populations largely ignored to date.